The most recently available statistics indicate that approximately 22.2 million people in the United States have asthma. Of these, about 55% experienced at least one attack in the year before the survey resulting in 1.9 million visits to emergency departments and 497,000 hospitalizations. The natural history of acute asthma is one of resolution and 70 to 80% of people rapidly clear their airway obstruction following treatment with 7.5 to 10.0 mg of nebulized albuterol. However, there is a subset of patients with recurrent severe episodes that are poorly responsive to this treatment and require admission to hospital for resolution. Although these patients represent a minority of asthmatics, they have persistent disease that accounts for the vast majority of expenditures for urgent care. Yet virtually nothing is known about them. In the present application, we wish to test the hypothesis that these individuals do poorly with albuterol because of genetic polymorphisms of their beta 2 adrenergic receptors (β2AR) that either influence severity and/or reduce responsiveness to short acting bronchodilators.